Plate boundaries Flashcards
Plates moving towards each other
Destructive
Plates moving away from each other
Constructive
Plates moving parallel to each other
Conservative
Oceanic crust
Low density of rock, mainly basalt, thin, newly created
Continental crust
High density of rock, mainly granite, thick, old
Mantle convection (convection currents)
Radioactive elements in the core of the Earth decay which produce a lot of thermal energy. This causes the lower mantle to heat up and rise, as the magma rises it cools down and becomes more dense and begins to sink back down to the core. These are convection currents. These convection currents push the plates
Slab pull
Old oceanic crust (which is the most dense plate) will submerge into the mantle. This pulling action drags the rest of the plate with it